Weed can make you feel euphoric and buzzed, or it can just make you want to melt into the couch like that girl in those anti-drug commercials. We asked a doctor about what causes different highs.

Weed is great but weed is also a mysterious creature. Why is it that sometimes, no matter how long you keep your greedy hands on your friend's joint and take many deep and very serious inhales, you just can't get high? Then other times, maybe even the very next day, after a half puff from a one-hitter, you're sitting there in a cold-sweat and completely baked?

While smoking can yield unpredictable results, edibles are another complicated monster. Rest assured, if you're planning to drink an entire bottle of weed lube, then you'll absolutely be fucked up fast. Since that isn't a predicament most of us will face, your biggest edible-related issue is likely waiting for it to kick in; this can turn into an intense test of self-control, where you're tempted to overeat yourself into a stupor, later realizing you've been staring at a blank wall for hours.

Beyond this delicate recipe of finding the right way to attain a successful high, there are even different kinds of highs, with the most common being head and body highs. The two are very different, with head highs described to me by Lola* as "incredibly trippy and fun, everything becomes more vivid. Everything is interesting and TV is amazing," and body highs described to me by Kara* as "extremely relaxing from my fingers to toes, it's like my insides are glitter and my chronic back aches go away."

While most people have experienced the two different highs, there's surprisingly very little available literature about them, aside from weed forums where contributors are busy educating lurkers that indica means "in da couch."

Broadly spoke to Dr. Aury Holtzman, a medical doctor based in Huntington Beach, California who specializes in marijuana and has evaluated over 11,000 patients to determine their medical marijuana needs, and asked him to explain the difference between those glorious head and body highs.

In order to understand why we get different kinds of highs, we need a cursory understanding of how our bodies get high in the first place. The human body has evolved to include an endocannabinoid system with various neurotransmitters and receptors. "It's like a lock and key," said Dr. Holtzman describing how neurotransmitters, the messenger chemicals in the brain, bind with receptors. Some neurotransmitters are believed to regulate specific processes—serotonin for mood, sleep and learning, and dopamine for the brain's "reward system."

In 1988, a cannabinoid receptor was discovered in the brain and its peripheries, suggesting that our brains already have a naturally-occurring neurotransmitter similar to those found in marijuana. That neurotransmitter native to the body is called anandamide and comes from the Sanskrit word for "bliss." It plays a role in the body that impacts pain management, depression, appetite, memory, and fertility. Dr. Holtzman simplifies it by saying, "It tends to make people feel good." Cannabinoids from cannabis plants bind with our natural brain receptors, activating the overall system and getting us high.

So, what happens in our bodies to make us experience different head and body highs?

One of the biggest factors is the way you ingest your weed. "When you smoke, the cannabinoids go straight into your lungs," said Dr. Holtzman. "They go right into your blood supply, into your brain, across the blood-brain barrier and then you get the high." It's different when you eat that phat pot brownie. "[The cannabinoids] don't go into your blood, they go to the liver and then the liver will convert the THC," said Dr. Holtzman. "You get a slightly different effect on the receptor." So basically, when cannabinoids go straight to your lungs, you're more likely to feel a head high. When they go through your liver, it's more of a body high.

Another thing that can affect your high is marijuana strain. Dr. Holtzman believes marijuana plants are very smart and over time they have evolved to contain different terpenes, which are essential oils that impact a plant's smell and strain. "The head versus the body high is due to the different terpene levels," explained Dr. Holtzman. Historically, there are two species of cannabis with different terpenes: indica and sativa. "Indica is known as the body high, with a focused calm feeling and sativas were known for the head high, used for more cerebral things," said Dr. Holtzman. "When you think of sativa, you think of enhanced, raised elevated but the side effects of sativas can be too much anxiety or panic attacks."

And while it may sound easy to determine your highs by your strains, it's become tougher over the years as all weed plant strains have become hybridized. "There are very few plants that would be pure indica or sativa," said Dr. Holtzman. "All these strains out there are hybrids but some give you more indica effects, other mores sativa effects." So if you're smoking an indica and experiencing more of a head high, there's a chance that your strain is more hybrid than your dealer led you to believe.

So what do you do when you've smoked or eaten too much? Kara* told me that when she needs to not be high anymore, she exercises. "It makes me feel like I'm burning out all the THC in my system," she said. I asked Dr. Holtzman if there is any validity to that and surprisingly, he said yes. "The exercise mobilizes your blood which helps you excrete [THC] faster." Which explains why you might not feel that edible if you're out skating or doing anything that isn't lying immobile on your couch while listening to Fetty Wap on vinyl.

"While medicating with THC, it's really important to stay hydrated and keep your electrolytes in balance," adds Dr. Holtzman. So the next time you got too baked and need to go somewhere and not seriously weird everyone out, do some jumping jacks and chug some water before heading out.